Compared to the normal appearance of the tongue muscles and the very low PD1 expression seen in the non-infected group (Figs. 1 and 2), the infected non-treated group showed severe infection with encysted larvae surrounded by thick intact capsules and moderate to severe inflammatory infiltration accompanied by high local PD1 expression (Figs. 1 and 3 and Table 2). The gene discussed is PDCD1; the disease is infection.